Abstract

Adsorption of and molecules on semiconducting single-walled carbon nanotubes is investigated using density functional theory. Both and molecules are found to bind to carbon nanotubes via physisorption. Electron charge transfer is found to be a major mechanism determining the conductivity change in carbon nanotubes upon exposure to and molecules. The calculated density of states is also considered to elucidate the differences in the and gas detection mechanism of carbon nanotubes.